Signal transmitting and lesion excluding heart implants for pacing, defibrillating, and/or sensing of heart beat

ABSTRACT

Devices, systems, and methods for treating a heart of a patient may make use of structures which limit a size of a chamber of the heart, such as by deploying a tensile member to bring a wall of the heart toward (optionally into contact with) a septum of the heart. The implant may include an electrode or other structure for applying pacing signals to one or both ventricles of the heart, for defibrillating the heart, for sensing beating of the heart or the like. A wireless telemetry and control system may allowing the implant to treat congestive heart failure, monitor the results of the treatment, and apply appropriate electrical stimulation.

CROSS-REFERENCES TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 11/536,553 filed Sep. 28, 2006, the full disclosure of which isincorporated herein by reference in their entirety.

BACKGROUND OF THE INVENTION

The present invention is generally directed to improved devices,systems, and methods for treatment of the heart. Exemplary embodimentsprovide implants and methods for alleviating congestive heart failureand other progressive diseases, for pacing (often biventricular pacing),for monitoring beating of the heart, and/or the like. Congestive heartfailure may, for example, be treated using an implant which excludesscar tissue and limits a cross section across a ventricle, with theimplant also being used to help in sensing the heart function and pacingor (as needed) defibrillating the heart.

Congestive heart failure (sometimes referred to as “CHF” or “heartfailure”) is a condition in which the heart does not pump enough bloodto the body's other organs. Congestive heart failure may in some casesresult from narrowing of the arteries that supply blood to the heartmuscle, high blood pressure, heart valve dysfunctions due to rheumaticfever or other causes, cardiomyopathy (a primary disease of the heartmuscle itself), congenital heart defects, infections of the hearttissues, and the like. However, in most cases congestive heart failuremay be triggered by a heart attack or myocardial infarction. Heartattacks can cause scar tissue that interferes with the heart muscle'shealthy function, and that scar tissue can progressively replace moreand more of the heart tissue. More specifically, the presence of thescar may lead to a compensatory neuro-hormonal response by theremaining, non-infarcted myocardium.

People with heart failure may have difficulty exerting themselves, oftenbecoming short of breath, tired, and the like. As blood flow out of theheart slows, blood returning to the heart through the vascular systemdecreases, causing congestion in the tissues. Edema or swelling mayoccur in the legs and ankles, as well as other parts of the body. Fluidmay also collect in the lungs, interfering with breathing (especiallywhen lying down). Congestive heart failure may also decrease the abilityof the kidneys to remove sodium and water, and the fluid buildup may besufficient to cause substantial weight gain. With progression of thedisease, this destructive sequence of events can cause the eventualfailure of the remaining functional heart muscle.

Treatments for congestive heart failure may involve rest, dietarychanges, and modified daily activities. Various drugs may also be usedto alleviate detrimental effects of congestive heart failure, such as byexpanding blood vessels, improving and/or increasing pumping of theremaining healthy heart tissue, increasing the elimination of wastefluids, and the like.

Surgical interventions have also been applied for treatment ofcongestive heart failure. If the heart failure is related to an abnormalheart valve, the valve may be surgically replaced or repaired.Techniques also exist for exclusion of the scar and volume reduction ofthe ventricle. These techniques may be involve (for example) surgicalleft ventricular reconstruction, ventricular restoration, the Dorprocedure, and the like. If the heart becomes sufficiently damaged, evenmore radical surgery may be considered. For example, a heart transplantor a ventricular assist device may be the most viable options for somepatients. These surgical therapies can be at least partially effective,but typically involve substantial patient trauma. While people with mildor moderate congestive heart failure may benefit from these knowntechniques to alleviate the symptoms and/or slow the progression of thedisease, less traumatic therapies which significantly increase the heartfunction and extend life of congestive heart failure patients hasremained a goal.

It has recently been proposed that a device be applied to or implant beplaced in the heart of certain patients with congestive heart failure soas to reduce ventricular volume. With congestive heart failure, the leftventricle often dilates or increases in size. This can result in asignificant increase in wall tension and stress. With diseaseprogression, the volume of the left ventricle gradually increases whileforward blood flow gradually decreases, with scar tissue often taking upa greater and greater percentage of the ventricle wall. By implanting adevice which brings opposed walls of the ventricle into contact with oneanother, a portion of the ventricle may be constricted or closed off,thereby reducing volume. By reducing the overall size of the ventricle,particularly by reducing the portion of the functioning ventriclechamber formed by scar tissue, the heart function may be significantlyincreased and the effects of disease progression may be at leasttemporarily reversed, halted, and/or slowed.

An exemplary method and implant for closing off a lower portion of aheart ventricle is shown in FIG. 1, and is more fully described in U.S.Pat. No. 6,776,754, the full disclosure of which is incorporated hereinby reference. As illustrated in FIG. 1, a patient's heart 24 has beentreated by deployment of an implant across a lower portion of the leftventricle 32 between septum 28 and a left wall or myocardium region 34.The implant generally includes a tensile member which extends betweenanchors 36 and 38.

A variety of alternative implant structures and methods have also beenproposed for treatment of the heart. U.S. Pat. No. 6,059,715 is directedto a heart wall tension reduction apparatus. U.S. Pat. No. 6,162,168also describes a heart wall tension reduction apparatus, while U.S. Pat.No. 6,125,852 describes minimally-invasive devices and methods fortreatment of congestive heart failure, at least some of which involvereshaping an outer wall of the patient's heart so as to reduce thetransverse dimension of the left ventricle. U.S. Pat. No. 6,616,684describes endovascular splinting devices and methods, while U.S. Pat.No. 6,808,488 describes external stress reduction devices and methodsthat may create a heart wall shape change. Each of these patents is alsoincorporated herein by reference.

While the proposed implants may help surgically remedy the size of theventricle as a treatment of congestive heart failure and appear to offerbenefits for many patients, still further advances would be desirable.In general, it would be desirable to provide improved devices, systems,and methods for treatment of congestive heart failure. It would beparticularly desirable if such devices and techniques could increase theoverall therapeutic benefit for patients in which they are implanted,and/or could increase the number of patients who might benefit fromthese recently proposed therapies. Ideally, at least some embodimentswould include structures and or methods for prophylactic use,potentially altogether avoiding some or all of the deleterious symptomsof congestive heart failure after a patient has a heart attack, butbefore foreseeable disease progression. It would be advantageous ifthese improvements could be provided without overly complicating thedevice implantation procedure or increasing the trauma to the patientundergoing the surgery, ideally while significantly enhancing thebenefits provided by the implanted device.

BRIEF SUMMARY OF THE INVENTION

The present invention generally provides improved devices, systems, andmethods for treating a diseased or at-risk heart of a patient.Embodiments of the invention may make use of structures which decreaseor limit a size of a chamber of the heart, such as by deploying atensile member to bring two walls of the heart (one of which is usually,but not necessarily the interventricular septum) into contact, thusdiminishing a circumference of the chamber. In addition to limiting adimension across the chamber, the implant may include an electrode orother structure for applying signals (often as electrical potential orvoltage, current, or the like) to one or both ventricles of the heart,such as for defibrillating the heart, pacing the heart, or the like. Inmany embodiments, the implant may sense motion, intercavity pressure,oxygen saturation, flow, activation potentials, or other measurements offunction or beating of the heart, optionally using the same electrodesand/or other sensor surface(s) of the implanted device. Exemplaryembodiments of the implant may be included within a hardwired and/orwireless telemetry and control system, allowing the implant to not onlytreat congestive heart failure and monitor the results of the treatment,but to apply appropriate electrical stimulation based on monitoredactivity of the treated heart.

In a first aspect, the invention provides a method for treating adiseased or at-risk heart. The heart has a first chamber bordered by aseptum and a wall. The heart has a second chamber separated from thefirst chamber by the septum. The method comprises deploying an implantthrough the septum. The implant includes a tensile member, and thetensile member is tensioned between the septum and the wall to limit adimension of the heart. Signals are transmitted with the implant.Optionally, the signals may pace the heart. The signals can also be usedfor defibrillation. The signals may alternatively be used to sensebeating and/or other functional measurements of the heart. Combinationsof any of the three of pacing, defibrillating, and sensing may also beprovided, so that the signals may comprise stimulation signals and/ormonitoring signals.

The tensile member will often pull the wall toward the septum while theimplant transmits the pacing signals transceptally. In many embodiments,the tensile member may be drawn into engagement with the septum. Thechamber will often comprise a left ventricle of the heart, with the walland septum engaging each other sufficiently to effectively exclude aportion of the wall and septum from the functioning left ventricle. Theexcluded portion will often comprise scar tissue.

The implant will often be used to facilitate biventricular pacing of theleft and right ventricles. The tensile member may extend through scartissue of the heart and a pacing lead may be included in the implant,with the pacing lead extending from the scar tissue adjacent the tensilemember to a functioning, contractile tissue remote from the tensilemember. In some embodiments, contractile heart tissue signals of theleft and/or right ventricle may be sensed using the leads of theimplant. The implant may also be used to defibrillate the left and/orright ventricle, with defibrillation voltage optionally beingtransmitted from (or from adjacent to) the tensile member via the scartissue, and/or from one or more electrode surfaces separated from thetensile member.

First and second anchors may affix the tensile member to the septum andwall of the heart, thus effectively sealing the septum around signalsthat are transmitted transceptally. Defibrillation signals may be passedfrom the implant to the heart by using an electrode surface of at leastone of the anchors, such as through use of an electrode surface alongthe anchors or the like. Where the implant extends through the wall, thesecond anchor may engage and apply heart defibrillation voltage to anepicardial surface of the wall. In some embodiments, a lead for pacingor sensing contractions may be deployed at a location which is separatedfrom that of the anchors. For example, the implant may optionally helpmeasure heart contractile signals along an epicardial surface of thewall or from the septum using such leads.

The implant will often be coupled to a processor having a first mode anda second mode. The implant in the first mode may monitor beating of theheart in response to sensed heart signals, and may transmit (wirelesslyor by hardwire) output signals indicative of beating of the heart. Theimplant in the second mode may pace or defibrillate the heart, with theimplant optionally having three modes to facilitate sensing, pacing, anddefibrillation.

In another aspect, the invention provides an implant for treating aheart. The heart has a first chamber bordered by a septum and a wall anda second chamber separated from the first chamber by the septum. Theimplant comprises a first anchor couplable to the septum a second anchorcouplable to the wall. Separation or distance between the second anchorand the first anchor can be constrained so as to limit a dimensionacross the first chamber of the heart. A pacing electrode surface,defibrillating electrode surface, and/or sensing surface may beprovided, or some other sensor may be included. A signal transmissionconductor extends between (often being just a portion of the distancebetween) the first anchor and the second anchor. The conductor iscoupled to the surface to allow electrical heart signal transmission.

The surface will often comprise a pacing and/or sensing electrodesurface. Insulation may extend along an axis between the anchors forisolating pacing and/or beat sensing signals from blood and adjacentheart tissue. A tensile member will typically couple the first anchor tothe second anchor so as to limit the separation therebetween, with theinsulation often covering at least a portion of the tensile member, andhence, the tensile member may also comprise the conductor. In otherembodiments, a separate conductor for transmitting signals may extendalong at least a portion of the tensile member with the insulationdisposed therebetween. The conductor may have single or multi-channelsignal transmission capabilities within the implant.

In many embodiments, the electrode surface may comprise a firstelectrode surface disposed along the first anchor. A second electrodesurface may be disposed along the second anchor. In such embodiments, adefibrillator power source may be coupled with the electrode surface(s).The power source may comprise a battery, and may be implanted in thepatient.

In some embodiments, the electrode surface may comprise a tip or surfaceof a pacing lead. A conductor may extend from the first anchor, thesecond anchor, and/or the tensile member to the pacing lead. A secondpacing lead and associated conductor may also be provided, with eachpacing lead optionally being disposed in an associated ventricle of theheart so as to provide biventricular pacing. Multiple leads may also beused in each ventricular.

A heartbeat signal processor may be coupled with the electrode surface,with the processor monitoring beating of the heart. Hardwired orwireless telemetry and/or control signals may be sent to or from theimplant. The implant may generally have a sensing mode and another mode,with transmission of hardwired or wireless signals from the implant inthe sensing mode indicating beating of the heart to an externalprocessor. In the other mode, the implant may provide stimulationsignals or potentials to the heart, such as by applying pacing ordefibrillating the heart.

In another aspect, the invention provides an implant for biventricularpacing of a heart. The heart has a first chamber with scar tissue, thefirst chamber bordered by a septum and a wall. The heart has a secondchamber separated from the first chamber by the septum. The implantcomprises an elongate tensile member having an access. A first anchor iscouplable with the tensile member to affix the tensile member to theseptum. A second anchor is couplable with the tensile member to affixthe tensile member to the wall. Tensioning of the tensile membereffectively excludes at least a portion of the scar tissue from thefirst chamber. A first pacing electrode surface is separated from thefirst anchor for positioning within the chamber beyond the scar tissue.A second pacing electrode surface is separated from the second anchorfor positioning within a second chamber beyond the scar tissue. Abiventricular pacing signal source is coupled with the first and secondelectrode surfaces.

In another embodiment, the invention provides an implant fordefibrillating the heart. The heart has a first chamber bordered by aseptum and a wall, and a second chamber separated from the first chamberby the septum. The implant comprises an elongate tensile member havingan axis. A first anchor is couplable with the tensile member to affixthe tensile member to the septum. A second anchor is couplable with thetensile member to affix the tensile member to the wall so thattensioning of the tensile member limits a dimension of the firstchamber. A first electrode surface is disposed along the first anchor,and a second electrode surface is disposed along the second anchor. Adefibrillation signal source is coupled with the first and secondelectrode surfaces.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view schematically illustrating a knownimplant and method for closing off a lower portion of a heart ventricle,as described in the background section.

FIG. 2 schematically illustrates a system according to an embodiment ofthe invention, in which an implant limits a dimension of a chamber ofthe heart, and in which anchors of the implant are used for signaltransmission, for example to defibrillate the heart when appropriate.

FIG. 2A is a schematic of a system related to that of FIG. 2, in whichleads extend from the implant to contractile tissue to facilitatebiventricular pacing and/or heart signal sensing using the implant.

FIGS. 3A and 3B illustrate examples of images of the heart and/ordevices disposed therein that may be used to direct deployment ofembodiments of the invention.

FIGS. 4A-4E are cross-sectional views schematically illustrating methodsfor accessing, identifying, and penetrating tissues for deployment ofthe implant system of FIGS. 2 and 2A.

FIGS. 5A and 5B are cross-sectional views schematically illustratinginitial deployment of an implant of the system of FIGS. 2A and 2B, withthe implant initially being deployed in an elongate configuration.

FIGS. 6A-6D illustrate deployment of an anchor for use in the implant ofFIG. 5B.

FIGS. 7A and 7B are cross-sectional views schematically illustratingshortening of the tensile member of FIG. 5B from the elongate initialconfiguration to a shortened deployed configuration so as to reduce asize of the left ventricle and effectively exclude at least a portion ofa scar tissue from the left ventricle.

FIG. 8 is a view showing a deployed implant after removal of thedelivery system.

FIG. 9 is a flow chart schematically illustrating a method for treatmentusing the implant system of FIGS. 2 and 2A, in which a mode of theimplant system changes from a monitoring mode to a stimulating mode inresponse to monitored heartbeat signals.

FIG. 10 is a cross-sectional view showing deployment of a pacing leadsof the implant system of FIG. 2A.

FIG. 11 schematically illustrates accessing the heart via a subxiphoidincision.

FIG. 12 illustrates a method for unloading of the heart with a doubleballoon catheter.

FIGS. 13A-13C schematically illustrate one variation of atransventricular implant and anchor system from a left ventricularapproach.

FIGS. 14A and 14B schematically illustrate another variation of atransventricular implant and anchor system from a right ventricularapproach.

FIG. 15 illustrates a double balloon catheter for unloading of the heartin the method of FIG. 10.

FIGS. 16A-16C schematically illustrate another variation of atransventricular implant and anchor system from a left ventricularapproach.

DETAILED DESCRIPTION OF THE INVENTION

The present invention generally provides improved devices, systems, andmethods for treatment of a heart. Embodiments of the invention may beparticularly beneficial for treatment of congestive heart failure andother disease conditions of the heart. The invention may find uses as aprophylactic treatment, and/or may be included as at least a portion ofa therapeutic intervention.

Myocardial infarction and the resultant scar formation is often theindex event in the genesis of congestive heart failure. The presence ofthe scar may, if left untreated, lead to a compensatory neuro-hormonalresponse by the remaining, non-infarcted myocardium. The systems,methods, and devices described herein may be applied to inhibit,reverse, or avoid this response altogether, often halting a destructivesequence of events which could otherwise cause the eventual failure ofthe remaining functional heart muscle.

Embodiments of the present invention may build on known techniques forexclusion of the scar and volume reduction of the ventricle. Unlikeknown techniques that are often accomplished through open surgery,including left ventricular reconstruction, ventricular restoration, theDor procedure, and the like, the treatments described herein will often(though not necessarily always) be implemented in a minimally invasivemanner. Embodiments of the invention can provide advantages similar tothose (for example) of surgical reconstruction of the ventricle,resulting in improved function due to improved dynamics, and bynormalizing the downward cycle initiated by the original injury andmediated by the neuro-hormonal disease progression response. In someembodiments, the implants and systems described herein may be includedwith other surgical therapies, such as by augmenting or replacing theimplantation of an implantable defibrillator, pacemaker, valve surgery,or the like.

Advantageously, the methods, devices, and systems described herein mayallow percutaneous left ventricular scar exclusion and ventricle volumereduction to be applied at any appropriate time during the course of thedisease. Rather than merely awaiting foreseeable disease progression andattempting to alleviate existing cardiac dysfunction, the techniquesdescribed herein may be applied proactively to prevent some or all ofthe heart failure symptoms, as well as to reverse at least a portion ofany existing congestive heart failure effects, to limit or halt theprogression of congestive heart failure, and/or to retard or preventcongestive heart failure disease progression in the future. Someembodiments may, for appropriate patients, limit the impact ofmyocardial infarction scar formation before heart failure ever develops.

Referring now to the illustration of FIG. 2, an exemplary implant system40 comprises an implant 42 and is used to treat a heart H of a patient.Implant 42 generally extends from within a right ventricle RV, through aseptum S, traverses a left ventricle LV and a wall W of the leftventricle, to an epicardial surface EP.

Implant system 40, implant 42, and heart H are schematically illustratedin FIGS. 2 and 2A. Although the implant is shown extending through anopen left ventricle, many embodiments will, when fully deployed, bringthe septum S and wall W together to effectively limit the size of leftventricle LV and exclude scar tissue. Nonetheless, some alternativeembodiments of the implants described herein may extend across apartially or fully open left ventricle, even when the system is fullydeployed.

As illustrated in FIG. 2, implant 42 is electrically coupled with asignal processor and/or signal generator (hereinafter “processor 44”)via one or more electrical conductors 46. Implant 42 generally comprisesa septal anchor 48, a wall anchor 50, and a tension member 52therebetween, and any one or more of these components may have activeelectrode surfaces which are electrically coupled to signal processorand generator 44 by associated conductors 46. As the tensile member 52and anchors 48, 50 may engage scar tissue, such anchor-mountedelectrodes may be suitable for defibrillation of the heart or the like.Pacing and sensing of the heart contractions may be facilitated by useof an electrode surface separated from anchors 48, 50 to engage adjacentcontractile tissues, often through the use of separate lead structuresas described below. Electrograms measured using electrodes engagingcontractile tissues may be of greater diagnostic value than thoserecorded via scar tissue, although alternative embodiments may make useof such scar-engaging electrodes to obtain heart cycle data.

Processor 44 may be partially or fully implanted under a skin SK of thepatient. In embodiments having at least a portion of the signalprocessing and/or generating performed outside of the skin SK,communications between implant 42 and an external processor 54 (orbetween the implant and an implanted processor) may be effected using awireless transceiver 56. Such communications may also allow externalrecording and/or monitoring of heart activity or implant performance,external commands to be transmitted to the implant, or the like. A powersource 58 such as a battery or the like may be implanted below the skin,with the power source optionally being chargeable through the skin usingknown inductive medical device battery charging structures. In someembodiments, most or all of the data processing may be handled by theexternal processor 54. Some embodiment may also make use of wiresextending through the skin SK to transmit signals to or from the heart Hvia implant 42, and/or to supply power to the implant.

Exemplary embodiments of anchors 48, 50 will selectively coupletissue-engaging electrodes of implant 42 with processor 44. Otherportions of implant 42, including portions exposed to blood within theheart, organs surrounding the heart, and the like may be electricallyisolated from signals transmitted to or from the heart by electricalinsulation materials and/or a housing. Separate tissue-engaging regionsof implant 42 may be separately coupled to processor 44 for measuringheart contractions at different locations in the heart, for transmittingseparate stimulation potentials to different heart tissues, for applyingbipolar potentials across the implant, and/or the like.

Processor 44 may comprise digital and/or analog circuitry, oftencomprising an integrated digital signal processing circuit programmablewith machine-readable computer programming instructions or code. Thecode will typically be embodied in a tangible media of the processor,using a non-volatile memory, a random access memory, or the like.Suitable processing structures that may be modified for use as processor44 in system 40 include many of those processors now used in implantablecardiac stimulation systems such as implantablecardioverter-defibrillators and the like. Wireless transmission systemsincluded in system 40 may be adapted or modified from structuresincluded in these same known systems, or wireless transmissionstructures included in neural stimulation devices, implantable insulinpumps, glucose monitoring devices, and in a variety of other implantablestructures. Other embodiments may rely entirely on internal signalprocessing and generation in some or all modes of operation, or the dataprocessing and energy storage may be fully self-contained within theimplant. A wide variety of internal and/or external centralized ordistributed data processing techniques might be implemented. Powersources developed for these and other devices may be used as powersource 58, or a proprietary power source may be included.

Wireless energy and/or data transmission to or from the implant 42 mayreduce the complexity and trauma of system deployment, and a variety ofwireless energy transmission arrangements for the components of system40 may be employed. For example, a battery within implant 42 may providesufficient energy to sense local electrograms, to pace the heart, andthe like. In some embodiments, electromagnetic energy for heart beatmonitoring and pacing may be transmitted from outside the patient bodyand to the implant 42 from an external power source. Suitable techniquesfor such energy transmission may include those (or be modified fromthose) developed by Advanced Bionics Corporation of Sylmar, Calif. Thesignificantly greater energies associated with defibrillation of theheart will often be provided by a battery implanted outside the hearttissue and electrically coupled to implant 42 by an electricalconductor.

Referring now to FIGS. 2 and 2A, a variety of different signals may besent between heart H and processor 44 via implant 42. In manyembodiments, surfaces of the implant may comprise electrode surfaces andmay be used to sense cardiac contraction signals, the sensed signalstypically comprising electrograms. Electrode surfaces of implant 42 mayalso be used to transmit stimulation signals and/or voltages fromprocessor 44 to the heart, such as for defibrillation, pacing, and thelike. Where implant 42 is used to limit a size of a left ventricle andexclude scar tissue, at least some of the tissues engaged by the implantstructure may comprise or form non-contractile scar tissue.Defibrillation potentials may be applied through such scar tissue, sothat surfaces of anchors 48, 50 and elongate member 52 may be suitablefor use as electrode surfaces. In contrast, for transmission of pacingsignals or voltages from processor 44 to tissues of the heart H and forcardiogram sensing, it will often be advantageous to include conductorsor leads 60 extending beyond the scar tissue to engage contractiletissue of the heart. While shown schematically in FIG. 2A as engagingendocardial tissues, pacing signals or voltages may optionally beapplied to the myocardium, along an epicardial surface, or the like.

The cardiac monitoring and treatment functions and structures ofprocessor 44 can make use of known technologies, particularly thosedeveloped for existing implanted heart monitoring and treatment devices.In some embodiments, implant 42 (and any associated leads thereof) mightbe electrically coupled to one or more lead ports of an implantableheart monitoring and stimulation device such as the CONTAK RENEWAL®cardiac resynchronization therapy defibrillator (CRT-D), available asModel H135 from Guidant (now owned and managed by Boston ScientificCorp. of Massachusetts). This device provides cardiac resynchronizationtherapy for the treatment of heart failure by providing electricalstimulation to the right and left ventricles to synchronize ventricularcontractions, and provides ventricular tachyarrhythmia therapy to treatventricular tachycardia (VT) and ventricular fibrillation (VF), rhythmsthat are associated with sudden cardiac death (SCD). The CONTAK RENEWAL®CRT-D features independent left ventricle and right ventrical channelsthat are independently programmable, and that may be coupled to leftventricle and right ventricle leads of implant 42. Such devices alsoallow monitoring of the heart rate, activity, and the like, and may alsogenerate defibrillation signals or voltages (with defibrillationvoltages optionally being transmitted through anchor surfaceelectrodes). Processor 44 might alternatively comprise an InSync® ICD(implantable cardioverter defibrillator) from Medtronic, which wasdesigned to combine defibrillation and resynchronization therapy, and tomonitor the electrical conduction system of the heart and deliverlifesaving therapy for ventricular arrhythmias and defibrillationimpulses if necessary. Still further alternatives include the Frontier®CRT Biventricular Stimulation Device (from St. Jude Medical, Inc., ofSt. Paul, Minn.) a multiple port, multi-chamber device for stimulatingthe heart in a biventricular or left-ventricular fashion to promoteresynchronization and improved hemodynamic performance.

Patients who are candidates for left ventricular reconstruction may beat much higher risk of sudden cardiac death due to ventricularfibrillation. In such patients, implantation of system 40 having thecapabilities of an ICD may increase life expectancy. Such benefits maycome largely or primarily from automatically shocking the patient into aregular rhythm soon after ventricular fibrillation or a very fastventricular tachycardia is sensed by processor 44. One or more implants42 may be used to treat the left ventricle of a single patient, andtheir one or more anchor(s) 50 on the anterior free wall of the leftventricle could be used as an effective shocking electrode (withmultiple anchors 50 optionally being connected together to serve as asingle electrode). These anchors may be located on the anterior part ofthe free wall of the left ventricle apical to all viable muscle in theventricle. A defibrillating shock might be (for example) deliveredbetween such a free wall anchor(s)/defibrillating electrode(s) and adefibrillating electrode placed in the right atrium, particularly aright atrium electrode located in the posterior aspect of the heart. Anyof a wide variety of commercially available defibrillating electrodesstructures might be coupled to the right atrium, with the lead couplingthe right atrium electrode optionally (though not necessarily) beingintegrated into implant 42, such as by traversing the septum using alead extending along or through the tension member. This arrangement maybe capable of providing high voltage gradients to most or allventricular muscle in the heart. These two general electrode positionswill be well positioned in space to provide an effective defibrillationpulse using defibrillation shock energies, including those commonlydelivered from commercially available ICDs.

Left ventricular reconstruction using the techniques described hereinmay also improve heart function in patients that suffer a largeanterior/apical infarct due to left anterior descending artery (“LAD”)occlusion or severe narrowing, often by changing the physical dimensionsof the left ventricle to enable the surviving heart muscle to work moreeffectively. Improvement in heart function may also be achieved byreducing the amount of non-synchronous contraction of the muscles in theleft ventricle. The infarct may interrupt the normal activation pathwaysfor the heart, resulting in contractions in different parts of the leftventricle being somewhat out of sync with each other. This lack ofsynchronicity both increases the work of the heart and decreases itsability to pump blood. Pacing the left ventricle at two or more sitesusing the systems and methods described herein may result in a moresynchronous contraction that improves the pump efficiency of the heart.

Referring now to FIGS. 3A and 3B, deployment of the implants describedherein and implementation of the therapies will benefit from accurateand reliable identification of the margins separating the scar andviable, contractile myocardium. Such identification can be accomplished,for example, using pre-operative imaging, catheter-sensed activationpotentials, pacing thresholds, ultrasonic imaging characteristics,biomarkers, or a variety of other tissue imaging and/or characterizationmethodologies. In general, it will be beneficial to provide informationto the physician deploying the system to allow accurate characterizationof selected locations as substantially comprising scar tissue orsubstantially comprising a viable contractile tissue. Additionally, thegeometry of the chambers of the heart, and particularly the leftventricular chamber, should be clearly imaged to facilitate the desiredreduction in size of the left ventricular chamber. This imaging may beaccomplished by one imaging modality or by a combination of differentimaging modalities. Exemplary imaging modalities which may be employedfor identification of the heart geometry and/or tissue characterizationinclude: echocardiography (including intracardiac echocardiography(“ICE”) and/or extra-cardiac echocardiography (such as transesophagealechocardiography and/or transthoracic echocardiography (“TTE” and “TEE”,respectively) or the like), intra- or extra-vascular endoscopy,fluoroscopy, or any of a variety of alternative existing or new imagingtechniques, either alone or in combination.

FIGS. 3A and 3B illustrate an example of ICE showing the geometry of theheart chambers, including a right atrium RA, a portion of the rightventricle RV, and the left ventricle LV along with some of the hearttissues bordering these chambers. FIG. 3B illustrates an intracardiacechocardiography image in which a catheter device within the ventriclecan be seen.

Deployment of the structures described herein may also benefit fromsensors that can be used to monitor the procedure, such sensors ideallyproviding a real-time assessment of the progress of the treatment andperformance of the heart during deployment and/or as deployment iscompleted. The goal of deployment will often be to achieve a desiredreduction in size of a chamber (typically the left ventricle), whileavoiding overcorrection (which might otherwise induce acute diastolicdysfunction). Such functional assessment sensors may comprise pressuresensors, hemodynamic sensing systems, strain sensors, oxygen saturationsensors, biological marker detectors, and/or other sensors measuringheart function to permit a quantitative assessment of efficacy of theprocedure as it is implemented.

Referring now to FIGS. 4A-4E, exemplary techniques and structures foraccessing and penetrating the septum and left ventricular wall can beunderstood. First summarizing these steps, it will be advantageous toidentify, engage, and temporarily hold the device in alignment with adesired position on the right ventricular septum, as schematicallyillustrated in FIG. 4A. Identification or characterization of theengaged tissue will also be advantageous. The septum will be penetratedas can be understood with reference to FIG. 4B, and the system issteered across the left ventricular chamber as illustrated in FIG. 4C.The system engages one or more target locations on the left ventricularwall as shown in FIG. 4D. The engaged tissue may be characterized andthe system repositioned as needed, with the system being held inengagement with the left ventricular wall if found to be at anappropriate or designated position, with the system optionally attachingor temporarily affixing itself to the left ventricular wall. The leftventricular wall may then be perforated, penetrated, or otherwisetranscended as illustrated in FIG. 4E.

In more detail, referring now to FIG. 4A, an access and deploymentsystem 70 includes a catheter 72 and a penetrating/sensing perforationdevice 74. In some embodiments, separate devices may be used forpenetrating the heart tissues and characterizing the tissues. Here,catheter 72 accesses the right ventricle RV in a conventional manner,typically by advancing the catheter over a coronary access guidewire. Adistal end of catheter 72 is aligned with a candidate location along theright ventricular surface of the septum S by a combination of axialrotation of the catheter and distal/proximal positioning of thecatheter, as shown by the arrows. Positioning of the catheter isdirected with reference to imaging (as described above) and when the endof the catheter is aligned with the candidate location a perforationdevice 74 is advanced distally so that a distal end of the perforationdevice contacts the septum S.

Perforation device 74 may characterize or verify that the candidatelocation is appropriate, for example, by determining a pacing thresholdat the candidate site. Scar tissue ST may have a pacing threshold whichdiffers sufficiently from a viable tissue VT to allow the physician toverify that the candidate site comprises scar tissue and/or is otherwisesuitable. If the candidate site is not suitable, the perforation device74 may be withdrawn proximally to disengage the perforation device fromthe septum S, and the catheter may be repositioned as described above toa new candidate site.

Catheter 72 may comprise a commercially available steerable sheath orintroducer. Deflection of catheter 72 may be effected using one or morepull wires extending axially within the catheter body. Suitableintroducers include devices that can be introduced transcutaneously intoa vein or artery. Suitable steerable sheaths may generally comprise atubular catheter body with an open working lumen. The open lumen can beused as a conduit for passing another catheter into the patient body, orfor introducing another device (such as a pacing lead) into the patientbody. Exemplary steerable sheaths for use in system 70 may include thosecommercially available from the Diag division of the St. JudeCorporation. Preferably, the working lumen of catheter 72 will be in arange from about 5 F-11 F.

Regarding perforating device 74, one embodiment would comprise adeflectable or steerable catheter body (ideally comprising a 2 F-3 Fcatheter) with a metallic bullet-shaped electrode at its distal end. Thedistal electrode is connected to a signal wire that terminates in aconnector outside the body. Electrogram amplitudes recorded from thedistal electrode can be used to help determine if the distal tip islocated over scar tissue or over viable tissue. Efficacy incharacterization of engaged heart tissues (between scar tissue andviable heart tissue) may be enhanced by recording the differentialsignal between the tip electrode and a band electrode located less than1 cm from the distal electrode.

Pacing from the distal tip can be employed to help avoid perforationthrough viable myocardium. For most patients, such a perforation sitewould be counter-indicated. If the heart can be paced from the tip usinga 10V amplitude pacing pulse, then viable myocardium will generally bedisposed within about 5 mm of the tip. When the proper penetration sitehas been identified, then the distal tip is electrically coupled to anelectrosurgical power source unit, and penetration is enabled byapplying power to the tip in cut mode. At proper power settings, thisperforation method can allow a clean perforation channel to be createdwithout the tearing that can otherwise occur with physical perforationof the septum or free wall.

Once an appropriate site has been identified and verified, the system isheld in alignment with the candidate site, and may optionally be affixedtemporarily at the verified site. Perforation device 74 is advanceddistally into and through septum S as illustrated in FIGS. 4B and 4C. Insome embodiments, perforation device 74 may have a sharpened distal tip,a rotatable helical or screw structure, or other mechanical attributesto facilitate penetration into and perforation through the myocardium.Alternative energy delivery elements (such as a variety ofelectrosurgical energy units, laser energy, or the like) may also beprovided. In some embodiments, system 70 may employ components similarto or modified from known septum traversing systems used for accessingthe left ventricle.

As can be understood with reference to FIGS. 4C and 4D, once perforationdevice 74 has penetrated through the septum S, manipulation of thecatheter 72 under the guidance of the imaging system allows theperforation device to be steered across the left ventricle LV and intoengagement with a target location along the wall of the left ventricle.The tissue at this target location may be characterized using a sensorof perforation device 74, pacing of the engaged tissue, or the like, andthe end of the perforation device repositioned as needed. The preferredlocation for deployment of the implant may be along or adjacent to scartissue ST. In some embodiments, system 70 may be used for positioning ofa lead at a location separated from the axis of the implant tensioningmember. System 70 also allows for epicardial lead placement by advancingthe perforation device 74 endocardially through septum S and themyocardium of the left ventricular wall W until it is located on theepicardial surface of the heart. The perforation device 74 and/or leadmay be at least temporarily fixed at that location and tested for properpacing effect, as can be understood with reference to FIGS. 4E and 5B.

The access and deployment system 70 described above with reference toFIGS. 4A-4E may be supplemented with or replaced by a number ofdiffering system components. For example, as can be understood withreference to FIG. 5A, a balloon catheter 80 or other sealing structuremay be used, optionally being advanced within catheter 72 and/or overperforation device 74. The balloon of balloon catheter 80 may bepositioned within the myocardium of septum S or the left ventricularfree-wall W to anchor the deployment system temporarily to the hearttissue and control blood loss, particularly blood loss through the leftventricular wall into the extra-cardiac space. In some embodiments, twoseparate balloons may be used to seal both the septum and the leftventricular wall. Balloons may also be used with or as anchors of theimplant device.

Still further alternative structures may be employed, perforation device74 may have any of a variety of sensors, including pressure sensors andthe like. System 70 will often comprise high contrast structures toenhance imaging, such as by including materials having highradio-opacity, echo-density, or the like. As noted above, perforationdevice 74 may have or be used with a cutting, drilling, or othermechanism to help in tissue penetration. Still further alternativestructures may be used for steering and positioning of the deploymentsystem and perforation device. For example, rather than manuallymanipulating or steering catheter 72 to position and orient the implant,the deployment system may employ robotic surgical techniques such asthose now being developed and/or commercialized for manipulation ofcatheters. Magnetic steering of the catheter end may also be employed,and any of a wide variety of mechanical steerable or pre-formed catheterstructures could be employed. Some or all of the components may accessthe left and/or right ventricular chambers using an epicardial approach,rather than the endovascular approach described above. A combination ofan extracardiac and intracardiac approach may also be employed, with thecomponents of the implant being introduced in any of a wide variety oftechniques. In some embodiments, implant 42 and/or other components ofthe system may be deployed in an open surgical procedure. Directlyaccessing at least the epicardial surface of the heart may significantlyfacilitate positioning and deployment of implant 42, particularly fordevelopment of implant system components and techniques, including thosewhich may later be deployed in a minimally invasive manner.

Referring now to FIGS. 5B and 6A-6C, implant 42 is deployed throughcatheter 72 of deployment system 70, with the implant initially beingdeployed in an elongate configuration extending across left ventricleLV. Anchors 48, 50 of implant 42 advance distally through a lumen ofcatheter 72 while the anchor is in a small profile configuration, asillustrated in FIG. 6A. Anchor 50 expands from the small profileconfiguration to a large profile configuration, which may be effected byaltering a distance between a distal end 82 and a shaft of tensionmember 52 using elongate bodies 84, 86 detachably coupled to the distalend 82 and tension member 52, respectively.

In general, anchors 48, 50 will be deployable through, over, or adjacentto the myocardium tissue penetrating components of deployment system 70.The anchors will attach to or otherwise engage the wall, usually byexpanding or inflating into a cross section larger than that of thepenetration through the heart tissue. A wide variety of anchorstructures may be employed, including structures that form a disk-shapedsurface or lateral extensions from an axis 90 of implant 42. As can beunderstood with reference to FIG. 60, an inflatable bladder 92 orballoon of appropriate shape may be used alone or in combination withother anchoring structures. If an inflatable bladder or balloon is used,it may be filled with a substance which is initially introduced as aliquid, but which reversibly or irreversibly solidifies. Suitable fillmaterials may, for example, comprise liquid silicone rubber, which canpolymerize at any of a variety of alternative desired rates depending onthe chemistry of the material used. Optionally, the material maysolidify over more than one hour, optionally over many hours or evendays at body temperatures. During a procedure, such an injected liquidcould be removed if desired, but the material would eventually solidify.Biological adhesives could also be delivered as fluid to fill a balloon,though cure times are relatively shorter for such materials. Suchmaterials would irreversibly solidify.

The septal and left ventricular wall anchors 48, 50 may be identical orsimilar in structure, or may differ to reflect the differences betweenthe epicardial and endocardial surfaces they engage. Fixation to thewall and septum will generally be sufficient to support the tension oftensile member 52, which will generally be capable of approximating thewall and septum, typically maintaining proximity or engagement betweenthese structures during beating of the heart. Anchors 48, 50 and tensilemember 52 will often comprise high-contrast materials to facilitateimaging, such as by including materials of sufficient radio-opacity,echo density, and the like.

In some embodiments, implant 42 may be used alone or with similar ornon-signal transmitting implants to effect volume reduction over alength, width, or volume of the ventricular wall. When at least aportion of the implant 42 is deployed using an epicardial approach, leftventricular anchor 50 will often be included in the components attachedfrom outside the heart, with tensile member 52 and/or anchor 48 beingattached to this epicardial component during deployment. Roboticstructures may be used to position the intracardiac or extracardiaccomponents, and/or to attach the two of them together.

Referring again to FIGS. 6A-6D, the exemplary anchor structure comprisesa Nitinol™ shaped memory alloy or other flexible material formed into atubular shaft. Axial cuts 94 may be formed along this tubular shaft,with the cuts having a desired length and being disposed near distal end82. Anchor 50 is advanced until the most proximal margin of cuts 94extends clear of the heart tissue. A retraction member 96 (optionallybeing releasable attached to the associated elongate body 86) fixed tothe inside of distal end 82 is retracted proximally, expanding the wallsof the tubular shaft radially into the circumferential series of arms98. Tissue engaging surfaces 100 of arms 98 may be substantiallyperpendicular to axis 90 of the implant. Arms 98 may have two generalcomponents, including the portion of the arm along tissue engagingsurface 100 and a slightly longer bracing portion of the arm 102extending away from the tissue engaging surface along axis 90. Theproportionate sizes of these two elements of arms 98 may bepre-determined by localized altering of the arm stiffness (effecting theplacement of living hinges) or the tubing material will otherwisepreferably bend so that the arms assume a desired shape. The deployedarms may have, for example, the pyramid shape shown with the tissueengaging surface 100 supported by angled portions 102 with apyramid-like force distribution, the angled bracing portions forming atriangular relationship with the surface of the heart wall.

Member 96 may remain within the deployed anchor, axially affixingtensile member 52 relative to the end of the anchor after deployment ofthe implant. This can help inhibit collapse of the arms 98. In someembodiments, arms 98 may be biased to the large cross section deployedconfiguration, such as by appropriate treatments to a shape memory alloyor the like. In such embodiments, member 98 or some other actuationstructure may restrain the anchor in a small cross sectionconfiguration, it may not remain within the deployed implant after it isexpanded.

As can be understood with reference to FIG. 60, once the anchor 50 isdeployed and in position, additional support elements may be positionedor deployed through the deployment system 70. For example, a spaceoccupying or expandable structure such as bladder 92 may be positionedor inflated within arms 98, internal support structures (optionallycomprising internal pyramid-like support arms) may be deployed. Theseptal anchor 48 will optionally have a structure similar to anchor 50,with the proximal and distal orientations of the arm structuresreversed.

While anchor 50 of FIGS. 6A-6D is shown as being integrated into atubular shaft of elongate tensile member 52, the anchor or fixationdevice may alternatively comprise a separate element introducedseparately over a guidewire or the like. Still further alternatives maybe employed, including fixation of the heart walls by placement ofmagnetic materials on or within the walls, with the bodies acting asanchors and the magnetic material acting as a tensile component so as tohold the walls in apposition.

Anchors 48 and/or 50 may optionally be drug eluting. For example,bladder or balloon 92 may have a porous surface capable of eluting asubstance from the film material. Alternatively, an outer surface of theballoon or the anchor structure itself may comprise a permanent orbiodegradable polymer or the like, such as those that have beendeveloped for drug eluting stents and available from a number ofcommercial suppliers.

Referring now to FIGS. 5B, 7A, and 7B, after anchors 48-50 are deployed,implant 42 may be shortened from its elongate configuration with arelatively large distance between the anchors along tensile member 52 toa shortened configuration. In some embodiments, the tensile member maycomprise a shaft of the tissue penetrating perforation device 74 (seeFIGS. 4A-4E). In other embodiments, tensile member 52 will comprise aseparate structure. In many embodiments, the tensile member and anchorswill remain permanently in the heart to hold the septum and leftventricular wall in apposition. To allow shortening of the tensilemember, excess length of the tensile member may be removed with thecatheter 72 and other components of the delivery system, and/or someportion of the length of the tensile member may remain in theextracardiac space outside the left ventricular wall. Optionally, aratchet mechanism may couple the septal anchor 48 to the tensile member52, with the ratchet mechanism allowing the separation distance betweenthe anchors to gradually decrease.

Referring now to FIGS. 6A, 6B and 8, tissue engaging surface 100 ofanchors 48, 50 may include an electrode surface 104. The electrodesurface of the anchor may act as a sensing surface for detecting heartcontraction, or may be used to apply stimulation voltage to the heart.For example, defibrillation potential may be applied to the heart usingat least the electrode surfaces (and optionally other surfaces of theimplant, including surfaces of the tensile member, other defibrillationelectrodes, and the like). The defibrillation potential will preferablycreate a voltage gradient of at least about 5 volts/cm throughout muchof the ventricles, often throughout the majority of the ventricles, andin some cases, throughout substantially all of the tissue of theventricles. Additional leads external from implant 42 may be used toprovide the desired gradients in some embodiments.

As noted above regarding FIG. 2A, implant 42 may also be used to applypacing signals or voltages to the heart. Such pacing voltages may,however, benefit from leads extending from the implant to a pacingelectrode surface sufficiently separated from the anchors and tensilemember of the implant as to be disposed viable and/or contractiletissue.

Referring now to FIGS. 8 and 9, once implant 42 is fully deployed, itmay effectively exclude a portion of the septum and/or left ventricularwall (particularly a portion including or comprising scar tissue) fromthe functional left ventricular chamber. Additionally, the signaltransmission capabilities of implant 42 may be used as a component of arhythm management system. Other components may be coupled to implant 42via an electrical conductor disposed in the epicardial space andextending from adjacent anchor 50, or may be incorporated into thestructure of the implant. Hence, implant 42 may have embodiments inwhich wireless signals are sent to and from the implant without hardwiring (as described above with reference to FIG. 2), and/or implant 42may be used as a cable/filar wire that is connected directly to othercomponents of the implant system.

Referring now to FIG. 9, a method of use 106 of the implant systemsdescribed herein may include monitoring of the heartbeat 108 with theimplant, either using electrode surface of anchors 48, 50, leads 60separated from the anchors, or the like (see FIGS. 2 and 2A). Byappropriate processing of the heartbeat signals sensed via the implant,the system may detect an arrhythmia 110 and may change the mode of theimplant system 112 in response. If the processor or communication froman external controller indicates that it is appropriate to do so, theimplant system may defibrillate and/or pace the heart 114. In manyembodiments, the implant will limit a cross section of the leftventricle and exclude scar tissue throughout the method 106. Hence, theinvention may combine left ventricular scar exclusion and volumereduction with heart signal monitoring and/or heart stimulation.

FIG. 10 shows an embodiment of the implant pacing structure that caneffectively improve the synchronicity of ventricular contraction. Afirst pacing electrode 122 is deployed from the right ventricular sideof the septum using a steerable catheter 124 having a pull wire 126.Pacing electrode 122 is placed in viable tissue to provide one pacinglocation for the ventricle. A second pacing electrode 128 is placed inviable tissue of the free wall W of the left ventricle LV, with thesecond electrode being deployed through the epicardium using aresiliently deflected or steerable catheter 130. In the illustratedembodiment shown in FIG. 10, pacing lead 128 is advanced within aconduit placed though the scarred ventricular septum S and scarredinfracted region of the anterior free wall W, the conduit optionallycomprising a sealable lumen of implant 42 or a temporary conduitstructure. For procedures done via a thoracotomy, the lead may bescrewed in place using standard methods. If the procedure is to be donetranscutaneously, steerable catheters 130, 124 or a deflectable sheath(similar to those described above) can be used to direct the pacing leadto the proper location on the epicardial surface and within rightventricle. The transcutaneously deployed pacing lead can be eitherscrewed in place or (for example, when the lead has a barded tip)otherwise advanced into the target viable tissue.

When used with commercially available pacemakers already designed formultiple site stimulation, the pacemaker leads can be individuallyconnected to the pacemaker ports on the implantable pacemaker device.Alternatively, the pacemaker leads may be connected together at a Yconnection or the like, and a common lead can be connected to thepacemaker head.

Referring now to FIG. 11, embodiments of the invention may be deployedusing a subxiphoid incision SI to access the heart, and/or theventricles of the heart. In some embodiments, additional access may beobtained through one or more intercostals space for one or moreinstruments. As shown in FIG. 12, a double balloon catheter 121 mayoptionally be used to unload the heart tissue. Double balloon catheter121 can provide inflow occlusion to decompress the ventricles, therebyreducing the systolic pressure. This may aid in reducing the ventricularvolume and/or in the exclusion of dysfunctional cardiac tissue. Doubleballoon catheter 121 may optionally be placed using open chest surgery.Alternatively, double balloon catheter 121 may be positioned usingminimal invasive techniques, such as via a femoral or subclavian vesselsor veins, and optionally being positioned percutaneously.

In some embodiments, double balloon catheter 121 may be positioned sothat one balloon is in the superior vena cava and one balloon is in theinferior vena cava, thus blocking most or even essentially all bloodflow from the body back to the heart. It may be easier to insert theballoon catheter either into the jugular vein or the femoral vein thanit is to place using a cardiac insertion site. An alternative (and in atleast some cases faster) way of off-loading the left heart is to inflatea suitably large compliant balloon in the pulmonary artery just abovethe pulmonic valve (proximal to the branching into the left and rightpulmonary arteries). A partially inflated balloon will tend to floatinto the pulmonary artery from the right atrium, since blood flowcarries it into that position. Hence, this may provide another method ofdecreasing preload on the ventricle.

With reference to FIGS. 13A-13C, one variation of a transventricularimplant and anchor system deployment from a left ventricular LVapproach. A sharpened, curved tissue piercing tubular body 123 piercesthe left ventricular wall, the septum, and extends back out through theright ventricular wall. This allows a ratcheted tension member 125 to beintroduced through the tissues of the heart within a lumen of tubularbody 123, with a first anchor 122 being attached to the tension memberafter insertion through the tubular body and expanded as described aboveor affixed after the distal end of the tension member extends free ofthe heart tissue. Regardless, once the tension member extends intoand/or through both ventricles, the tubular body 123 can be withdrawnproximally and a second anchor 129 can be moved distally along thetension member to engage the myocardial surface of the heart, as seen inFIG. 13B. Second anchor 129 may optionally pass through the lumen oftubular body 123 and expand radially, or may be coupled to tensionmember 125 after the tubular body is withdrawn.

An exemplary ratcheting interface between tension member 125 and secondanchor 129 may make use of a series of radial protrusions and/or detentsdisposed along an axis of the tension member. For example, the tensionmember may have slide surfaces which taper radially outwardly distallyalong the tension member to allow the anchor interface to slidesequentially over the slide surfaces in a distal direction, and detentsurfaces which are oriented distally to engage corresponding proximallyoriented surfaces of the anchor interface so as to inhibit proximalmovement of the anchor relative to the tension member. Second anchor 129may have a ratchet interface structure including (or derived from) thesealing components of a Touhy-Borst valve structure. Such an interfacemay resiliently deflect to pass the slide surfaces of the tension memberand may grab or engage the detent surface when the tension member ispulled distally. Such a valve structure may also be increased indiameter to release the tension member if desired and/or tightenedtowards its smallest diameter to immovably (and optionally permanently)affix the anchor relative to the tension member. Exemplary embodimentsof ratcheting tension member 123 may comprise polymers or metals,optionally comprising a polyester such as Mylar®, a thermoplastic suchas Nylon™, stainless steel, a shape memory allow such as Nitinol™, orthe like.

As shown in FIG. 13C, second anchor 129 can be positioned along tensionmember 123 so as to effectively exclude scar tissue from the leftventricle and/or reduce a volume of the left ventricle. Some portion oftension member 123 may be disposed within the right ventricle, rightventricle scar tissue may be excluded, and/or the volume of the rightventricle may also be reduced. The tension member may be severed using ablade or the like as shown schematically, though some of the tensionmember may extend into the extracardiac space. In alternativeembodiments using different surgical approaches (such as when using thecatheter-based systems described above), at least a portion of thetension member may extend into the right ventricle or the like.

Referring now to FIGS. 14A and 14B, another alternative embodiment of animplant 131 and deployment system makes use of a transventricularapproach from the right ventricle. A curved tension member 133 having adistal tissue penetrating end 135 and a proximal anchor 136 affixedthereto is introduced through the wall of the right ventricle, throughthe septum, across the left ventricle LV, and out through the leftventricular wall. The tension member 133 and affixed anchor 137 areadvanced distally so that the anchor engages the surface of the heart,and a second anchor 139 is attached by passing distal end 135 throughthe anchor. Second anchor 139 is ratcheted proximally along tensionmember 133 to exclude scar tissue and limit a size of the leftventricle, with the distal end and at least a portion of the tensionmember that is distal of the positioned anchor being severed and removedfrom the deployed implant. FIG. 15 shows an exemplary double ballooncatheter for use as described above with reference to FIGS. 11 and 12.FIGS. 16A-16C schematically illustrate another transventricular anchorsystem and deployment from a surgical site outside the heart similar tothat of FIGS. 13A-13C, using a tubular body 143 to position a tensionmember 143 to which first and/or second anchors 147, 149 are ratchetablyaffixed.

It should be noted that the systems and methods described herein forexcluding scar tissue and reducing a size of a chamber of the heart maymake use of a plurality of different implants of different types andeven different surgical approaches. For example, while systems mayinclude a plurality of implants deployed from a site outside the heart(such as the embodiments shown in FIGS. 13A-13C, 14A, 14B, and 16A-16C),alternative systems may include one or more implants of one or moretypes deployed from outside the heart, along with one or more implantsof one or more types deployed from inside the heart using a blood-vesselapproach. Systems with a plurality of implants deployed from outsideand/or inside the heart may benefit from any of a variety of imagingtechniques so that the implant systems effectively exclude scar tissueand limit a size of one or more heart chamber.

While exemplary embodiments have been described in some detail forclarity of understanding and by way of example, a variety ofmodifications, adaptations, and changes will be obvious to those ofskill in the art. Hence, the scope of the invention is limited solely bythe appended claims.

What is claimed is:
 1. An implant for treating a heart, the heart havinga first chamber bordered by a septum and a wall, the heart having asecond chamber separated from the first chamber by the septum, theimplant comprising: a first anchor coupleable to the septum; a secondanchor coupleable to the wall so that the second anchor contacts anepicardial tissue of the wall; a tensile member coupleable to the firstanchor and the second anchor so as to engage the septum and the wallsuch that the wall contacts the septum and is secured relative thereto;a pacing electrode, defibrillating electrode, and/or sensing surfacecoupled with the second anchor to apply signals to the epicardialsurface tissue of the wall; and a signal transmission conductor near atleast one of the anchors and coupled to the surface to allow heartsignal transmission between the implant and a tissue of the heart. 2.The system of claim 1, wherein the surface comprises a pacing and/orbeat sensing electrode surface, and further comprising insulation forisolating pacing and/or beat sensing signals from adjacent heart tissue.3. The system of claim 2, further comprising a conductor extending alongat least a portion of the tensile member, the insulation disposed atleast in part between the tensile member and conductor.
 4. The system ofclaim 1, further comprising an electrode surface along the second anchorsuch that the electrode surface contacts the epicardial surface of thewall.
 5. The system of claim 4, further comprising a defibrillatorsignal source coupled with the electrode surface.
 6. The system of claim1, further comprising a heartbeat sensing lead, wherein a conductorincluded in the lead and the lead having a length sufficient to extendfrom adjacent one of the anchors to a contractile tissue when theimplant is deployed, and further comprising a heartbeat monitoringsignal processor coupled with the surface.
 7. The system of claim 1,further comprising a first pacing lead, wherein a conductor included inthe first lead and the first lead having a length sufficient to extendfrom adjacent one of the anchors to a contractile tissue when theimplant is deployed, and further comprising: a second pacing lead; and abiventricular pacing signal source coupled with the first and secondleads.
 8. The system of claim 7, wherein the implant has a sensing modeand another mode, the implant in the sensing mode configured fortransmitting output signals indicating beating of the heart to theprocessor, the implant in the other mode configured for pacing the heartor defibrillating the heart.
 9. The system of claims 1, furthercomprising a signal source and/or signal processor wirelessly coupledwith the electrode surface.